postgresql: Update to version 11.3

Version 11.3 is the current stable relase.

Changes between 9.3 and 11.3:
- pg_receivexlog, pg_resetxlog and pg_xlogdump have been replaced with pg_resetwal
- ZIC config variable must be set when cross compiling
- disable systemd support
- ecpg is no longer needed for building
- MAKELEVEL must be set to 0 when called from another makefile
- Setting AC_CONFIG_AUX_DIR([config]) is no longer requried
- Decrease build time by removing unnecessary configure checks

Signed-off-by: Daniel Danzberger <daniel@dd-wrt.com>

libs/postgresql/patches/001-configure_fixes.patch

@@ -1,11 +1,41 @@
+diff --git a/configure.in b/configure.in
+index 9082c5b..2c04edc 100644
 --- a/configure.in
 +++ b/configure.in
-@@ -25,7 +25,7 @@ recommended.  You can remove the check f
- your responsibility whether the result works or not.])])
- AC_COPYRIGHT([Copyright (c) 1996-2016, PostgreSQL Global Development Group])
- AC_CONFIG_SRCDIR([src/backend/access/common/heaptuple.c])
--AC_CONFIG_AUX_DIR(config)
-+AC_CONFIG_AUX_DIR([config])
- AC_PREFIX_DEFAULT(/usr/local/pgsql)
- AC_SUBST(configure_args, [$ac_configure_args])
+@@ -2283,36 +2283,6 @@ if test "$with_python" = yes; then
+   CPPFLAGS=$ac_save_CPPFLAGS
+ fi
  
+-#
+-# Check for DocBook and tools
+-#
+-PGAC_PATH_XMLLINT
+-PGAC_CHECK_DOCBOOK(4.2)
+-PGAC_PATH_PROGS(DBTOEPUB, dbtoepub)
+-PGAC_PATH_PROGS(XSLTPROC, xsltproc)
+-PGAC_PATH_PROGS(FOP, fop)
+-
+-#
+-# Check for test tools
+-#
+-if test "$enable_tap_tests" = yes; then
+-  # Check for necessary modules, unless user has specified the "prove" to use;
+-  # in that case it's her responsibility to have a working configuration.
+-  # (prove might be part of a different Perl installation than perl, eg on
+-  # MSys, so the result of AX_PROG_PERL_MODULES could be irrelevant anyway.)
+-  if test -z "$PROVE"; then
+-    # Test::More and Time::HiRes are supposed to be part of core Perl,
+-    # but some distros omit them in a minimal installation.
+-    AX_PROG_PERL_MODULES([IPC::Run Test::More=0.87 Time::HiRes], ,
+-      [AC_MSG_ERROR([Additional Perl modules are required to run TAP tests])])
+-  fi
+-  # Now make sure we know where prove is
+-  PGAC_PATH_PROGS(PROVE, prove)
+-  if test -z "$PROVE"; then
+-    AC_MSG_ERROR([prove not found])
+-  fi
+-fi
+-
+ # Thread testing
+ 
+ # We have to run the thread test near the end so we have all our symbols